Summary: There is general consensus in the scientific literature that human-induced climate change has taken place and will continue to do so over the next century. The Fourth Assessment Report (AR4) of the Intergovernmental Plan on Climate Change (IPCC) concludes with “very high confidence” that anthropogenic activities such as fossil fuel burning and deforestation have affected the global climate. The AR4 also indicates that global average temperatures are expected to increase by another 1.1°C to 5.4°C by 2100, depending on the increase in atmospheric concentrations of greenhouse gases (GHGs) that takes place during this time. The projected effects of this increase in temperature are further reductions in global snow and ice cover and increases in sea level and total global precipitation over land. However, there is projected to be considerable variation in the level of warming by region as well as by time of day and time of year. In addition, models used for the IPCC projections forecast substantial changes in the temporal and spatial distribution of precipitation.

There is general consensus in the scientific literature that human-induced climate change has taken place and will continue to do so over the next century. The Fourth Assessment Report (AR4) of the Intergovernmental Plan on Climate Change (IPCC) concludes with “very high confidence” that anthropogenic activities such as fossil fuel burning and deforestation have affected the global climate. The AR4 also indicates that global average temperatures are expected to increase by another 1.1°C to 5.4°C by 2100, depending on the increase in atmospheric concentrations of greenhouse gases (GHGs) that takes place during this time. The projected effects of this increase in temperature are further reductions in global snow and ice cover and increases in sea level and total global precipitation over land. However, there is projected to be considerable variation in the level of warming by region as well as by time of day and time of year. In addition, models used for the IPCC projections forecast substantial changes in the temporal and spatial distribution of precipitation.